The dream is that it wouldn’t even be a purchase or placement check, but that there would be a tracker of how many different pieces are on the board, at all times. Even better would be to show the maximum, so a stats bar that says
7/10 tanks, or 3/3 bombers are currently on the board would be the optimum.
The cherry on top would be that the engine would even prevent the movement that violates the rule, but just having the feature in there at all like we do now, even with a couple errors, is very nice. Way better than nothing.
Anyway, thanks!!!